Whether or not writer Leigh Whannell, the writer of all four “Insidious” movies, intended it from the get-go, this horror series has become an exploration of the backstory of Elise Rainier (Lin Shaye), who has viewed her gifts for seeing, speaking to and confronting the dead as both a blessing and a curse. (Imagine the “Poltergeist” franchise, if it had been about Tangina, the spiritual housecleaner played unforgettably by Zelda Rubenstein.)
Making the movies all about Elise turned out to be a smart move, since Shaye brings such a depth of feeling and empathy to each film; it’s been said that horror movies are one of the few genres that where female characters consistently get to be active and interesting, and Shaye’s work in the series — including “Insidious: The Last Key,” the fourth and latest outing — has been the main reason to get enthusiastic about each new sequel.
Elise got killed off at the beginning of the first “Insidious,” but the series has managed to keep her alive with prequels and sidequels; “The Last Key” brings the character right up to the events of the first “Insidious,” but that’s not to say that if this one does well, we won’t see more of Shaye in another time-hopping prequel. (Particularly since this chapter gives her a new relative who’s also a poltergeist whisperer.)
This movie is, thankfully, much less interested in myth-building than it is in character development, giving us more of a look at where this woman comes from and how her abilities have shaped her life.
We open in a flashback to 1950s New Mexico, where young Elise (Ava Kolker, “Girl Meets World”) first realizes her gift for talking to the dead via the spirits of the prisoners being executed in the neighboring penitentiary, where her cruel father Gerald (Josh Stewart, “Shooter”) works as a guard.
While he wants Elise to suppress her paranormal activities, her mother, Audrey (Tessa Ferrer, “Grey’s Anatomy”), offers nothing but love and encouragement to Elise and her younger brother Christian (Pierce Pope).
Tragedy strikes at the hand of a demonic creature who passes between dimensions — much of the “Insidious” saga deals with a purgatory that Elise calls “the Further” — and Elise runs away from home to escape Gerald’s abuse.
But in 2010 (when “The Last Key” is set), she gets a call to return to that house to deal with the evil that still dwells there, and in doing so, she must encounter an embittered Christian (Bruce Davison), from whom she has been estranged for decades.
Whannell doesn’t break much new ground here — he’s written more shtick than usual for himself and Angus Sampson to play as the sidekicks, clearly to keep himself interested — but he and Shaye have created a fascinating character in Elise, and both of them apparently relish the opportunity to fill in some of the blanks in her backstory.
New-to-the-franchise director Adam Robitel (“The Taking of Deborah Logan”) and returning editor Timothy Alverson have fun with the mechanics of the PG-13 jump-scare; there’s one show-stopping scene in particular in which they make you wait for it, and wait for it, and it’s all the more satisfying when it finally comes.
The scares here are mild and kid-friendly, and there’s virtually no gore. Whannell’s screenplay touches on the idea of humanity being as monstrous as anything that goes bump in the night, but ultimately the worst things that men do here are blamed on supernatural forces beyond their understanding or control. It plays as a bit of a cop-out in a film that otherwise makes some interesting points about the power of love and family in a cold and chaotic universe.
Hardcore horror audiences won’t find much that’s frightening in “Insidious: The Last Key” — there’s not even that wonderfully unsettling shriek of violins under the title this time — but as a delivery system for more great work from Lin Shaye, it more than accomplishes its mission.